Determination of Lead in Aqueous and Organic Media by Atomic-Absorption Spectroscopy

Abstract

The sensitivities of lead in aqueous and organic media by atomic-absorption spectroscopy using lead lines 2170 Å, 2833 A, and 4058 Å, and an oxy-hydrogen or oxy-acetylene flame were studied. When lead in aqueous solution was complexed as K₂PbI₆ and the complex extracted into methyl isopropyl ketone, a threefold increase in sensitivity relative to the aqueous solution of lead (as lead nitrate) was obtained. Using a 178-mm-long adapter on the top of a Beckman integral aspirator—burner (oxy-hydrogen), a sensitivity (in ppm/1% absorption) of 0.007 and a standard deviation of 0.014 ppm were obtained with a sample containing 0.1 ppm lead. Results obtained with oxy-hydrogen and oxy-acetylene flames have been discussed, and the precision and detection limits indicated. A procedure to determine lead in ppb—ppm level by extracting lead as K₂PbI₆ in methyl isopropyl ketone has been prescribed.